SIEMENS CPU S7-412-3H External Fault & Redundancy Fault


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Dear All
We have SIEMENS PLC S7-412-3H redundant system having remote I/O modules connected with Profibus.

During commissioning when we Power up the system. The CPU's are showing External Fault & Redundancy Fault and CPU's are in stop mode (while On/Off Switch is in On Position) and other Modules showing BF1 & BF2.

I have tried to download the Project (as I do not have Backup in my PC) it is showing fault. Please anybody guide me to rectify this problem and how to communicate with these CPU's. I have the MPI cable and Simatic Manager version 5.5 SP2.